It uses the front-facing camera to detect when you're looking at your screen. When turned on, as long as the camera can detect your eyes looking towards the screen, the screen will remain unlocked. If you put your phone down or look away, it will turn off based on your screen timeout settings. In nutshell, it's a remote form of facial recognition.Try it in well lighted conditions..so that camera can recognize your face..camera k saamne jabtak rahoge to kaam karega, warna ni